Liquid sampling device



Sept. 9, 1969 TANSQNY LIQUID SAMPLING DEVICE Filed March 21, 1968 IVENTOR. JOHN R. TANSONY BY Aganc Patented Sept. 9, 1969 3,465,595 LIQUIDSAMPLING DEVICE John R. Tansony, 188 Markland Drive, Etobicake, Toronto,Ontario, Canada Filed Mar. 21, 1968, Ser. No. 714,848 Int. Cl. G01n1/00; F16k 15/.00

US. Cl. 73-421 6 Claims ABSTRACT OF THE DISCLOSURE This inventionrelates to a liquid sampling device with a submersible element wherebysuccessive samples may be taken from a bath of sewages, for example, atpredetermined depths therein and at predetermined times; such samplesthen being removed automatically from the submersible element or samplerto a remote testing or analysis station without the need for withdrawingthe sampler from the liquid.

As is known in the prior art, a liquid sampling device according to thepresent invention may include a receptacle or container immersible inliquid to be sampled; the container including only one inlet for theliquid governed by a one-way check valve to allow liquid to enter thecontainer under the hydrostatic pressures obtaining in the bath. Thecontainer also includes a vent connectable to an air line for ventingthe air displaced by the entering liquid and through which, alternately,the container may be pressurized to close the check valve and to expelall or part Of the contained liquid through an outlet of the containerconnectable by a conduit to a testing or analysis station usuallysituated externally of the liquid bath.

It is accordingly a broad object of the invention to provide an improvedliquid sampler offering certain advantages over the prior art samplers.

For example, it may be desired to obtain liquid samples for analysisfrom a bath of liquid wherein certain solids are present, as, forexample, in sewage, which may interfere with the obtaining of the sampleand/ or the operation of the sampling device.

Thus, it is a further object to provide a liquid sampler in the form ofa submersible container wherein liquid may enter freely therein butwherein undesirable lumps of solid matter are excluded from entry.

It is a still further object to provide a sampler having an inlet forliquid from a bath thereof wherein the inlet is so shaped as to resistentry of undesirable solids as aforesaid and which is also readilycloseable to prevent escape of the contained liquid through the inlet.

It is a still further object to provide a sampler having such an inletwherein closure thereof tends to expel any solids seeking to enter thesampler back into the bath.

It is a yet further object to provide a sampler wherein the inlet isreadily collapsible under air pressure within the sampler to preventescape of the contained liquid as aforesaid and wherein the inlet isalso limitedly expansible under hydrostatic pressure of the liquid, uponventing of said interior, to permit liquid to enter the sampler from thebath.

It is a still further object to provide a sampler, the interior of whichis readily connectable to venting and pressurizing means as aforesaidand having an outlet connectable to a receptacle for receiving sampleliquid from the sampler. Such receptacle may conveniently be locatedremote from the sampler such as, for example, adjacent apparatus forventing air from and pumping air into the sampler.

Accordingly the invention provides a submersible liquid sampler in theform of a container having an inlet for admitting liquid to be sampledto the interior of the container, an air venting and pressurizingconnection, and an outlet for sample liquid displaced from the interiorof the container to a remote testing station upon air pressurizationwithin the container; the inlet having a substantially slit-shapedresilient orifice normally biased towards a substantially closedposition and being expansible to a limited extent under hydrostaticpressure of the liquid to admit it to the container interior, whenvented, and being also readily collapsible to close the orifice underair pressurization of the container interior substantially to seal saidinlet.

Other objects of the invention, more or less broad than the foregoing,will become apparent from the following description of the parts,principles, and elements constituting the invention given herein solelyby way of example and with reference to the accompanying drawingswherein:

FIG. 1 is a schematic view of the instant sampler positioned in a bathof liquid showing ancillary venting and pumping means together with aremote testing or analysis station;

FIG. 2 is an enlarged transverse cross-sectional view of the sampler;

FIG. 3 is a perspective part-broken view of the inlet forming part ofthe instant sampler;

FIG. 4 is a side cross-sectional view of the inlet with its orificeopen;

FIG. 5 is a side cross-sectional view of the inlet with its orificeclosed and showing progressive collapsing thereof under the effect ofincreasing air pressure.

The instant invention provides a liquid sampler for obtaining samples ofliquid from a desired location within a bath of liquid. It should beunderstood that the expression bath of liquid is only used for the sakeof clarity to indicate a form of containment for the liquid. The liquidin question may, thus, be contained within an artifically constructedreceptacle such as a sewage tank or reservoir or it may be within anaturally bounded container such as in a river, canal, lake, or sea. Inany event, the invention is particularly concerned with the obtaining ofsamples of liquid from a bath of liquid which contains lumps of solidsin suspension, such as sewage, although it will be apparent that theinstant liquid sampler may also be utilized in liquids not containingany suspended lumps of solids.

The instant liquid sampler 10 is shown schematically in FIG. 1 of thedrawings as being suspended at a predetermined depth and location belowthe surface of the liquid 12 to be sampled.

In order to obtain samples without withdrawing the sampler from theliquid, facilities are provided at a convenient location to enablesamples to be transmitted from the sampler to a testing or analysisstation 14 remote from the sampler; such facilities including an airpumping and venting line 16 to the sampler 10 together with a furtherline 18 for conducting samples from the sampler to the aforesaid testingstation 14.

The sampler 10 itself illustrated in more detail in FIG. 2 comprises acontainer having a liquid inlet opening including a check valve whichfunctions in a manner more fully explained herein. In the embodimentillustrated, the container is of bell-shaped configuration cast of asuitable metal. More specifically, the container comprises a bell-shapedcover 20 detachably and hermetically clamped to a co-operating base 22,the base being provided with an opening 24 surrounded by a circularcollar 26 having inturned edges and forming part of the aforesaid inlet.Sealing ring 27 is located about the collar 26 between the base 22 andthe cover 20 of the container. The cover is provided with an integralapertured flange 28 for connecting the assembled container to suitablemeans, such as the wall 30 shown in FIG. 1, whereby the container may bepositioned at a desired predetermined depth and location within theliquid to be sampled.

The cover 20 is also provided with an air vent 32 in the apex thereofconnectable by a suitable coupling to air line 16 for venting airdisplaced from the interior of the container by liquid entering throughthe inlet and also for pumping air into the container. The cover 20 alsoincludes an outlet 34 located adjacent the lower edge of the coverconnectable by a suitable coupling to line or conduit 18 for conductingliquid expelled from the interior of the container to the testingstation 14 when air is pumped into the container.

The liquid inlet opening referred to above comprises the opening 24 inthe container base together with the aforesaid check valve.

It should be appreciated that, since the sampler is particularlyadvantageously utilized in the obtaining of liquid samples from a bathof liquid containing suspended solids, means must be provided not onlyto act as a check valve closeable when the sample is being transmittedunder air pressure to the testing station but also to act as a screen toprevent the entry of undesirable solids into the interior of thecontainer.

Accordingly the check valve forming part of the liquid inlet is alsodesigned to function as a screen for the purposes aforesaid.Specifically, the inlet includes a funnelshaped tapered tube 36 narrowedto a resilient slit-shaped orifice 38 at its downstream end and,preferably, the whole tube is formed of an elastomeric material such asnatural or synthetic rubber. The tube 36 is secured at its upstream endabout the collar 26 by means of a clamping clip 40.

From the foregoing description of the tube 36 and as clearly shown inthe drawings, it will be seen to resemble a short length of hose whichhas a basic cylindrical conformation but is flattened at its downstreamend; the cylindrical form being retained at its upstream end Where it issecured to the collar 26. The flattening aforesaid imparts a duckbillconfiguration to the downstream end of the tube 36 narrowing its bore tothe slit-shaped orifice 38 which is limitedly expansible under thehydrostatic pressure of liquid entering the container but is readilycollapsible under the influence of air pressure within the container toseal the inlet.

Moreover, the tapered or duckbill configuration of the downstream end ofthe inlet enables the orifice 38 to be progressively collapsed underincreasing air pressure within the container as illustrated in FIG. 5.It Will also be readily apparent from the foregoing description that theorifice remains in its slit-shaped configuration between open and closedpositions thereof whereby the entry of undesirable solids to theinterior of the container through said orifice is prevented even whenthe orifice is open.

Thus, the provision of a resilient orifice in the liquid inlet passageserves both as a screen and a check valve. Furthermore, the taperedconfiguration of the inlet adjacent the orifice enables a squeezingaction to be imparted between the interior surfaces of the side walls ofthe tube, under closing air pressure within the container, to tend toexpel any solids back towards the upstream end of the tube should anysuch solids enter the tube.

Operation of the sampler is carried out in the following manner inrespect of the obtaining of a liquid sample from a bath of liquid, forexample, sewage; the apparatus ancillary to the sampler itself being asshown schematically in FIG. 1 of the drawings.

Referring to the apparatus as shown schematically in FIG. 1, it shouldbe appreciated that some convenient switching or valve means 44 isprovided at the end of the air line 16 remote from the sampler 10whereby said line may be selectively vented to atmosphere or connectedto a pump for pressurizing the interior of the container. Such valve orswitching means may, for example, comprise a solenoid-operated valve ora simple mechanical three-way valve.

Consider as an initial condition that the aforesaid valve 44 is switchedto vent the air line 16 to atmosphere at which time the interior of thecontainer will be full of liquid. The valve 44 is then switched to theair pump to force air into the interior of the container through the airvent 32 in the apex of the cover 20 thereof. This pressurization of thecontainer interior achieves two results; firstly, the increasingpressure within the container progressively collapses the side walls ofthe inlet tube 36 adjacent the orifice 38 thereof thereby sealing theorifice whilst at the same time the liquid entrapped within thecontainer interior is forced through the outlet 34 to the remote testingor analysis station 14 via the associated conduit 18. Further increasein air pressure further seals the inlet orifice 38 whilst expelling allof the contents of the container to the testing station whilst at thesame time the squeezing action of the duckbill portion of the inletserves to expel any solids back towards the upstream end of the inletshould any such solids have entered into the tube. Thus, during thisstep of the cycle, the inlet is sealed to prevent any of the entrappedliquid within the container from being expelled through the inlet andensuring that all of such entrapped liquid is conducted to the testingstation.

After all of the entrapped liquid has been expelled from the interior ofthe container as aforesaid, the valve 44 is switched from the pumpingmeans to vent the air line 16 to atmosphere. Release of the air pressurewithin the container interior to atmosphere will enable liquid to enterthe interior of the container under hydrostatic pressure thereof throughthe inlet. As explained hereinbefore, the inlet orifice 38 is limitedlyexpansible under such hydrostatic pressure to admit liquid from the bathof liquid whilst still retaining its substantially slit-shapedconfiguration and thereby preventing any undesirable solids fromentering into the container interior. After a short period of time, thecontainer interior will have completely refilled with liquid at whichtime the cycle of operations may be repeated as aforesaid to expel thecontents to the testing or analysis station.

It will be appreciated that the sampling procedure outlined above may berepeated automatically at any desired time intervals and thus, forexample, a series of sample tests or analyses may be carried out withina sewage tank during any one day by a completely automated processwithout any need to interfere with the sampler whatsoever.

What I claim is:

1. A liquid sampler comprising:

a container submersible in a bath of liquid to be sampled; an elongatedinlet for conducting liquid from the bath into the container, said inletincluding an elongated tapered tube of resilient material disposedwithin said container providing a passage communicating between theinterior and exterior thereof;

lips on the downstream end of said tube providing an orifice relativelyfreely spreadable to a substantially slit-shaped configuration by andunder hydrostatic pressures obtaining in said bath permitting relativelyfree flow of liquid therethrough into the container, said lips beingstrongly resistant to further spreading and enlargement of said orificerestricting passage of lumps of solids therethrough;

an air vent connectable to an air line for venting air displaced byliquid entering the container and, alternately, for deliveringcompressed air into the con tainer, and

an outlet through which liquid is expellable from the container by thecompressed air aforesaid;

said tube being closeable by said compressed air to occlude the saidorifice and the said passage.

2. A liquid sampler as claimed in claim 1 wherein said tube is sealinglysecured, at its upstream end, about an aperture provided in thecontainer and constituting part of said inlet.

3. A liquid sampler as claimed in claim 1 wherein said lips are biasedto retain the substantially slit-shaped configuration of the orifice inand between its open and closed positions to prevent the entry of solidsthrough said orifice to the interior of the container at all times.

4. A liquid sampler as claimed in claim 1 wherein said tube ispredisposed to progressive collapse longitudinally thereof from saidorifice towards the upstream end of the hose under increasing pressureof air within said container.

5. A liquid sampler as claimed in claim 1 wherein:

said container comprises a cover detachably and hermetically sealed to abase, and

the upstream end of said tube is sealingly secured about an apertureprovided in said base.

6. A liquid sampler as claimed in claim 5 wherein:

said air vent is disposed at the top of said cover, and

said outlet is disposed adjacent the bottom of said cover.

References Cited UNITED STATES PATENTS 615,751 12/1898 Sands 137--525.12,986,098 5/1961 Trout et al. 137525.1 3,120,128 2/1964 Snyder.

S. CLEMENT SWISHER, Primary Examiner U.S. Cl.X.R.

